import pygame
from game_items import*
class HudPanel(object):
    """指示器面板类"""
    margin=10#精灵之间的间距
    white=(255,255,255)#白色
    gray=(64,64,64)#灰色
    reward_score=100000#关卡奖励分值
    level2_score=10000#关卡级别2的预设分值
    level3_score=50000#关卡级别3的预设分值
    record_filename="record.txt"#保存最好的成绩
    def __init__(self,display_group):
        """构造方法
        :param display_group:面板中的精灵要被添加到的显示精灵组
        """
        #游戏属性
        self.score=0#得分
        self.lives_count=3#生命计数
        self.level=1#关卡级别
        self.best_score=0#最好成绩
        self.load_best_score()

        #创建图像精灵
        #状态精灵
        self.status_sprite= StatusButton(("pause.png","resume.png"),display_group)
        self.status_sprite.rect.topleft=(self.margin,self.margin)
        #炸弹精灵
        self.bomb_sprite=GameSprite("bomb.png",0,display_group)
        self.bomb_sprite.rect.x=self.margin
        self.bomb_sprite.rect.bottom=SCREEN_RECT.bottom-self.margin
        #生命计数精灵
        self.lives_sprite=GameSprite("lives.png",0,display_group)
        self.lives_sprite.rect.right=SCREEN_RECT.right-self.margin
        self.lives_sprite.rect.bottom=SCREEN_RECT.bottom-self.margin

        #创建标签精灵
        #分数标签
        self.score_label= Label("%d"%self.score,32,self.gray,display_group)
        self.score_label.rect.midleft=(self.status_sprite.rect.right +self.margin,
                                        self.status_sprite.rect.centery)
        #炸弹标签
        self.bomb_label= Label("X 3",32,self.gray,display_group)
        self.bomb_label.rect.midleft=(self.bomb_sprite.rect.right +self.margin,
                                        self.bomb_sprite.rect.centery)
        #生命计数标签
        self.lives_label= Label("X %d"%self.lives_count,32,self.gray,display_group)
        self.lives_label.rect.midright=(SCREEN_RECT.right-self.margin,
                                        self.bomb_label.rect.centery)
        #调整生命计数精灵位置
        self.lives_sprite.rect.right=self.lives_label.rect.left-self.margin
        #最好成绩标签
        self.best_label= Label("Best:%d"%self.best_score,36,self.white)
        self.best_label.rect.center=SCREEN_RECT.center
        #状态标签
        self.status_label= Label("Game Over!",48,self.white)
        self.status_label.rect.midbottom=(self.best_label.rect.centerx,
                                        self.best_label.rect.y-2*self.margin)
        #提示标签
        self.tip_label= Label("Press spacebr to play again.",22,
                                self.white)
        self.tip_label.rect.midtop=(self.best_label.rect.centerx,
                                    self.best_label.rect.bottom + 8*self.margin)

    def show_bomb(self,count):
        """显示炸弹数量
        :param count:要显示的炸弹数量
        """
        #设置炸弹标签文字
        self.bomb_label.set_text("X %d" % count)
        #设置炸弹标签位置
        self.bomb_label.rect.midleft=(self.bomb_sprite.rect.right+self.margin,
                                    self.bomb_sprite.rect.centery)

    def show_lives(self):
        """显示生命计数"""
        #设置标签文字
        self.lives_label.set_text("X %d" % self.lives_count)
        #设置标签位置
        self.lives_label.rect.midright=(SCREEN_RECT.right-self.margin,
                                        self.bomb_label.rect.centery)
        #调整精灵位置
        self.lives_sprite.rect.right=self.lives_label.rect.left-self.margin

    def increase_score(self,enemy_score):
        """增加游戏得分
        :param enemy_score:摧毁敌机的分值
        :return:增加 enemy_score后,关卡级别是否提升
        """
        #游戏得分
        score=self.score+enemy_score
        #判断是否奖励生命
        if score // self.reward_score !=self.score // self.reward_score:
            self.lives_count +=1
            self.show_lives()
        self.score=score
        #最好的成绩
        self.best_score=score if score > self.best_score else self.best_score
        #关卡级别
        if score <self.level2_score:
            level=1
        elif score <self.level3_score:
            level=2
        else:
            level=3
        is_upgrade=level!=self.level
        self.level=level
        #修改得分标签内容和位置
        self.score_label.set_text("%d" % self.score)
        self.score_label.rect.midleft=(self.status_sprite.rect.right+self.margin,
                                    self.status_sprite.rect.centery)
        return is_upgrade
    
    def save_best_score(self):
        """将最好成绩写入record.txt"""
        file=open(self.record_filename,"w")
        file.write("%d" % self.best_score)
        file.close()

    def load_best_score(self):
        """从record.txt加载最好成绩"""
        try:
            file =open(self.record_filename)
            txt =file.readline()
            file.close()
            self.best_score=int(txt)
        except(FileExistsError,ValueError):
            print("文件不存在或者类型转换错误")

    def panel_pause(self,is_game_over,display_group):
        """面板暂停
        :param is_game_over:是否因为游戏结束需要暂停
        :param display_group:显示精灵组
        """ 
        #判断是否已经添加精灵，如果是直接返回
        if display_group.has(self.status_label,self.tip_label,self.best_label):
           return
        #根据是否结束游戏决定要显示的文字
        text ="Game Over!" if is_game_over else "Game Paused!"
        tip="Press spacebar to"
        tip +="play again." if is_game_over else"continue."
        #设置标签文字
        self.best_label.set_text("Best:%d"% self.best_score)
        self.status_label.set_text(text)
        self.tip_label.set_text(tip)
        #设置标签位置
        self.best_label.rect.center=SCREEN_RECT.center
        best_rect=self.best_label.rect
        self.status_label.rect.midbottom=(best_rect.centerx,
                                            best_rect.y-2*self.margin)
        self.tip_label.rect.midtop=(best_rect.centerx,
                                    best_rect.bottom+8*self.margin)
        #添加到精灵组
        display_group.add(self.best_label,self.status_label,self.tip_label)
        #切换精灵的状态
        self.status_sprite.switch_status(True)

    def panel_resume(self,display_group):
        """面板恢复
        :param display_group:显示精灵组
        """ 
        #从精灵组移除3个标签精灵
        display_group.remove(self.status_label,self.tip_label,self.best_label)
        #切换精灵状态
        self.status_sprite.switch_status(False)

    def reset_panel(self):
        """重置面板"""
        #游戏属性
        self.score=0
        self.lives_count=3
        #标签显示
        self.increase_score(0)
        self.show_bomb(3)
        self.show_lives()
         